So, not only is Russia involved in a major attempt to prevent Islamic lunatics from Syria and Iraq from attacking his own country, but he has a big debt to pay to Turkey. Here's my suggestion of something that the whole world could do to deal with both problems.
This is a map of the traditionally Kurdish areas, stretching from Turkey to Iran:
I am proposing that it is time that a Kurdish state be recognized in this area (perhaps, for political reasons, excluding the territory in Iran.) This would place a buffer state between Russia and ISIS, which would be highly opposed to any ISIS expansion, and at the same time finally penalizing the Turks for their century-long persecution of the Kurds.
In return for international support for this action, which would be highly beneficial for Russia's security, we should get Putin to accept what is obvious: Bashir al Assad is congenitally incapable of governing his country. His government must be replaced by one with some hope of leading Syria out of its current chaos, perhaps picked by the six nations and Iran that forged the Iranian nuclear deal, and with a firm commitment of support from them. There is no hope of a decent resolution of the Syrian situation while the pathetic Assad remains at the head of his government; we all know this. So, let's move on: an independent Kurdistan and a government capable of handling Syria. What could there possibly be to lose with a deal like this, which, by the way, represents what is going to inevitably happen one way or the other, with much more carnage, the longer it lasts?